Adds DevTools commands for forced viewport override.

third_party/WebKit/LayoutTests/inspector-protocol/emulation/device-emulation-test.js

 function setMetaViewport(override)
 {
     var VIEWPORTS = {
         "w=320": "width=320",
         "w=dw": "width=device-width",
         "w=980": "width=980",
         "none": "no viewport (desktop site)"
     };
 
     var viewport = VIEWPORTS["none"];
@@ skipping 185 matching lines @@
 
 InspectorTest.applyEmulationAndReload = function(enabled, width, height, deviceScaleFactor, viewport, insets, noReload, callback)
 {
     if (enabled) {
         var params = {};
         params.width = width;
         params.height = height;
         params.deviceScaleFactor = deviceScaleFactor;
         params.mobile = true;
         params.fitWindow = false;
-        params.scale = 1;

[dgozman, 2016/08/29 20:45:36]

Please revert.

[Eric Seckler, 2016/09/12 13:58:00]

Done.

         params.screenWidth = width;
         params.screenHeight = height;
         params.positionX = 0;
         params.positionY = 0;
         if (insets) {
             params.screenWidth += insets.left + insets.right;
             params.positionX = insets.left;
             params.screenHeight += insets.top + insets.bottom;
             params.positionY = insets.top;
         }
@@ skipping 33 matching lines @@
     InspectorTest.emulateAndGetMetrics(width, height, deviceScaleFactor, viewport, insets, noReload, callback);
 
     function callback()
     {
         InspectorTest.log(InspectorTest._deviceEmulationResults.join("\n"));
         InspectorTest.completeTest();
     }
 };
 
 };